PDF TDC Part III Practical (Lab Work)

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TDC Part III

Practical (Lab Work)

Department of Chemistry

L.S COLLEGE MUZAFFARPUR B. R. A. BIHAR UNIVERSITY

Dr. Priyanka

TOPIC:- PREPARATION OF COORDINATION

COMPOUNDS (Sodium tris (oxalato) ferrate (III)

complex; Na

3

[Fe(C

2

O

4

)

3

])

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PREPARATION OF COORDINATION COMPOUNDS Sodium tris (oxalato) ferrate (III) complex; Na

3

[Fe(C

2

O

4

)

3

]

Objective

To prepare sodium tris (oxalato) ferrate (III) complex.

Theory

Mixing of FeCl

3

and KOH in minimum amount of water forms hydrated ferric oxide slurry. And when this slurry is added to the hot solution of sodium oxalate, a greenish-brown solution of Iron (III) oxalate obtained, which on slow evaporation gives greenish crystals of sodium tris (oxalato) ferrate (III).

FeCl₃+3 NaOH Fe(OH) ₃+ 3NaCl

Fe(OH) ₃+ 3H₂C₂O₄+ 3NaOH Na₃[Fe(C₂O₄)₃] + 6H₂O

Requirements

Apparatus: Electronic weighing machine, beaker 500 mL, beaker 250 mL, Bunsen burner, desiccator, filtration apparatus, conical flask, funnel, glass rod, pair of tongs, tripod stand, watch glass, water bath, wire guaze.

Required chemicals: Ferric chloride 2.50 g

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Sodium hydroxide 2.75 g

Oxalic acid 3.00 g

Procedure

I. Preparation of ferric hydroxide: Separately dissolve 2.5 g of FeCl3 and 1.75 g of sodium hydroxide in 1-2 mL of water. Now add dodium hydroxide solution to ferric chloride solution to make brown colour slurry with stirring. This slurry is the precipitate of Fe(OH)3. Filter the

precipitate of ferric hydroxide in Bruckner funnel and wash it with small amount of hot water 2and 3 times.

II. Preparation of sodium tris (oxalato) ferrate (III): Dissolve 3g of oxalic acid in 10-15 mL of hot water then add 1 g of NaOH. Transfer ferric hydroxide in this hot solution with constant stirring. Dissolve Fe(OH)3 in hot solution, taking 3 moles of oxalic acid per 1 mole of Fe(OH)3. This will produce dark greenish-brown solution of iron (III) oxalate. Filter the solution and concentrate the green filtrate on water bath and obtain green crystal of sodium tris (oxalato) ferrate (III).

Structure of sodium tris (oxalato) ferrate (III)

2.3.1.5. Result

The yield of sodium tris (oxalato) ferrate (III) is ... g.